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High Dose SPINRAZA was studied in the 3-part DEVOTE trial to evaluate its safety and efficacy1,2
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The first-ever FDA-approved treatment for SMA

For patients of all ages1,3
~10 years of treating patients1
Patients treated with SPINRAZA in the US have a collective ~16,700 years of treatment experience4ϯ
From 0 days to 86 years old, patients across a broad range of ages have taken SPINRAZA5‡§

†Based on consented patients from a real-world sample in the US who are or have ever been treated with SPINRAZA through April 2026.4

‡Based on patients treated with SPINRAZA in the US through April 2026.5

§Pivotal studies did not include adult patients. Clinical studies did not include sufficient numbers of subjects aged 65 and over to determine whether they respond differently than younger subjects.1

FDA, Food and Drug Administration; SMA, spinal muscular atrophy.

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High Dose SPINRAZA
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Product Fact Sheet

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Patient Guide

INDICATION

SPINRAZA® (nusinersen) is indicated for the treatment of spinal muscular atrophy (SMA) in pediatric and adult patients.

IMPORTANT SAFETY INFORMATION

Coagulation abnormalities and thrombocytopenia, including acute severe thrombocytopenia, have been observed after administration of some antisense oligonucleotides. Patients may be at increased risk of bleeding complications.

In the sham-controlled studies for patients with infantile-onset (Study 1) and later-onset (Study 2) SMA who received Low Dose Regimen (12 mg loading doses/12 mg maintenance doses), 24 of 146 SPINRAZA-treated patients (16%) with high, normal, or unknown platelet count at baseline developed a platelet level below the lower limit of normal, compared to 10 of 72 sham-controlled patients (14%). Two SPINRAZA-treated patients developed platelet counts <50,000 cells per microliter, with the lowest level of 10,000 cells per microliter recorded on study day 28. In patients who received High Dose Regimen (50 mg loading doses/28 mg maintenance doses), decreases in platelet counts were also observed.

Renal toxicity, including potentially fatal glomerulonephritis, has been observed after administration of some antisense oligonucleotides. SPINRAZA is present in and excreted by the kidney. In Study 1 and Study 2, 71 of 123 SPINRAZA-treated patients (58%) had elevated urine protein, compared to 22 of 65 sham-controlled patients (34%).

Laboratory testing and monitoring to assess safety should be conducted. Perform a platelet count, coagulation laboratory testing, and quantitative spot urine protein testing at baseline and prior to each dose of SPINRAZA and as clinically needed.

Severe hyponatremia was reported in an infant treated with SPINRAZA requiring salt supplementation for 14 months.

Cases of rash were reported in patients treated with SPINRAZA.

SPINRAZA may cause a reduction in growth as measured by height when administered to infants, as suggested by observations from the controlled study. It is unknown whether any effect of SPINRAZA on growth would be reversible with cessation of treatment.

The most common adverse reactions in the Low Dose Regimen (≥20% of SPINRAZA-treated patients and ≥5% more frequently than in control patients) that occurred in the infantile-onset controlled study were lower respiratory infection and constipation. Serious adverse reactions of atelectasis were more frequent in SPINRAZA-treated patients (18%) than in control patients (10%). Because patients in this controlled study were infants, adverse reactions that are verbally reported could not be assessed. The most common adverse reactions that occurred in the later-onset controlled study were pyrexia, headache, vomiting, and back pain. Post-lumbar puncture syndrome has also been observed after the administration of SPINRAZA.

The most common adverse reactions in the High Dose Regimen (≥10% of SPINRAZA-treated patients and ≥5% more frequently than control patients from Study 1) that occurred in patients with infantile-onset SMA were pneumonia, COVID-19, pneumonia aspiration, and malnutrition. COVID-19 was not discovered at the time of Study 1.

Please see full Prescribing Information.

As a courtesy, our full Prescribing Information is also available en Español. For prescribing decisions, please refer to official approved labeling.

References

1. SPINRAZA. Prescribing Information. Biogen; 2026. 2. Finkel RS, Crawford TO, Mercuri E, et al. High-dose nusinersen for spinal muscular atrophy: a phase 3 randomized trial. Nat Med. 2026;32(3):1095-1104. doi:10.1038/s41591-025-04193-6 3. U.S. FDA approves Biogen’s SPINRAZA™ (nusinersen), the first treatment for spinal muscular atrophy [press release]. Biogen. December 23, 2016. Accessed March 19, 2026. https://investors.biogen.com/news-releases/news-release-details/us-fda-approves-biogens-spinrazatm-nusinersen-first-treatment 4. Biogen, Data on File as of 04/26. 5. Biogen, Data on File as of 04/26.

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